<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>计算器</title>
</head>
<body>
    <div id="app">
        <div class="input-num">
            <button>
                -
            </button>
            <span></span>
            <button>
                +
            </button>
        </div>
        <img src="http:www.itheima.com/images/logo.png" alt=""/>
    </div>
    <script src="https://cdn.jsdelivr.net/npm/vue/dist/vue.js"></script>
    <script>
        var app =new Vue({
            el:"#app",
            data:{
                num:1
            },
            methods:{
                add:function(){
                    //console.log('add');
                    if(this.num<10){
                        this.num++;
                    }else{
                        alert('别点啦，最大啦！');
                    }
                },
                sub:function(){
                    //console.log('sub');
                    if(this.num>0){
                        this.num--;
                    }else{
                        alert('别点啦，最小啦！');
                    }
                }
            },
        })
    </script>
</body>
</html>